Tau-Fyn Interaction and Alzheimer's Disease

Tau-Fyn 相互作用与阿尔茨海默病

基本信息

批准号：
10292907
负责人：
Jonathan R Roth
金额：
$ 1.62万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2021-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10292907
关键词：
3-Dimensional AMPA Receptors Ablation Affect Affinity Age Alzheimer&apos s Disease Alzheimer&apos s disease model Alzheimer&apos s disease patient Alzheimer&apos s disease therapeutic Amyloid beta-Protein Automobile Driving Behavioral Assay Binding Biological Assay Biological Models Cognitive Cognitive deficits Dementia Dendrites Dendritic Spines Disease Progression Electroencephalography Epilepsy Functional disorder Genetic Glutamates Goals Hippocampus (Brain)Impaired cognition In Situ In Vitro Knock-out Knockout Mice Lead Learning Ligation MAPT gene Measures Mediating Mediator of activation protein Membrane Modeling Molecular Morphology Mus Mutate Mutation N-Methyl-D-Aspartate Receptors N-Methylaspartate Nerve Degeneration Neurites Neurofibrillary Tangles Neuronal Dysfunction Neurons PXXP Motif Pathogenesis Peptides Phenotype Phosphorylation Phosphotransferases Population Predisposition Proline-Rich Domain Proteins Proto-Oncogene Proteins c-fyn Public Health Role SH3 Domains Scientist Seizures Signal Transduction Structure Synapses System Techniques Testing Therapeutic Vertebral column Work abeta toxicity base behavior test beta amyloid pathology career cognitive testing density excitotoxicity extracellular familial Alzheimer disease gabazine hyperphosphorylated tau immunocytochemistry in vivo inhibitor/antagonist insight member mouse model multi-electrode arrays novel strategies novel therapeutic intervention osmotic minipump overexpression postsynaptic prevent relating to nervous system skills tau Proteins tau interaction therapeutic target therapy development trafficking

项目摘要

Project Summary/Abstract Alzheimer’s disease (AD) is the leading cause of dementia worldwide and its impact will increase exponentially as the population ages. New therapeutic approaches are desperately needed to treat AD. The microtubule- associated protein Tau is has been heavily studies because it aggregates into neurofibrillary tangles within neurons, one of the hallmarks of AD. Genetic knockout of Tau is protective in several models of AD, highlighting its potential as a therapeutic target for AD. Interestingly, Tau reduction also prevents network hyperexcitability, which occurs early in AD and may contribute to neurodegeneration, in these models. Similarly, in a primary neuron culture system, Tau reduction prevents amyloid-β (Aβ) toxicity and glutamate or NMDA-induced excitotoxicity. In short, Tau reduction is protective in a variety of systems, but the mechanism by which it does so is currently unknown. Tau’s central proline-rich region, which is hyperphosphorylated in AD, has several PxxP motifs that mediate binding with SH3 domain–containing proteins including the nonreceptor tyrosine kinase Fyn. Fyn is also an important mediator of network hyperexcitability, as it phosphorylates AMPA and NMDA receptors to strengthen their signaling and regulates dendritic spine dynamics. Exogenous Aβ activates Fyn at the postsynaptic density, leading to NMDAR phosphorylation and excitotoxicity in neurons. Diverse evidence indicates that Tau’s interaction with Fyn could be a critical mediator of Aβ toxicity. Genetic knockout of either Tau or Fyn prevents Aβ toxicity in primary neurons, hyperphosphorylated Tau has a higher affinity for Fyn, and Tau mediates trafficking of Fyn to dendrites in vivo, leading to Aβ-induced cognitive deficits and network hyperexcitability. However, the idea that the Tau-Fyn interaction is a critical mediator of Aβ toxicity has not been directly tested, which is the goal of this project. My overarching hypothesis is that the Tau-Fyn interaction is a critical mediator of Aβ-induced structural and functional abnormalities. I will test this hypothesis using a peptide inhibitor of the Tau-Fyn interaction, Tau-PxxP5/6, developed by previous members of the Roberson lab. I developed a proximity ligation-based assay to confirm that Tau-PxxP5/6 inhibits endogenous Tau-Fyn interaction in situ and found that it prevents Aβ-induced neurite degeneration and membrane trafficking dysfunction. Here, I will determine if Tau-PxxP5/6 prevents Aβ-induced deficits in dendritic spine morphology using 3D morphometric analysis and Aβ- and gabazine-induced network hyperexcitability using multi-electrode arrays. I will also determine if the Fyn-binding region of Tau is the critical region of Tau that mediates Aβ toxicity by transducing Tau knockout neurons with different mutated Tau constructs to prevent Fyn binding. In addition to in vitro studies, I will determine if Tau-PxxP5/6 prevents cognitive deficits, epileptiform activity and seizure susceptibility in vivo using the hAPPJ20 mouse model of AD. The proposed work will provide insights into the molecular mechanisms of Aβ toxicity and could provide a promising therapeutic strategy to treat AD.

项目概要/摘要阿尔茨海默病 (AD) 是全球痴呆症的主要原因，其影响将呈指数级增长随着人口老龄化，迫切需要新的治疗方法来治疗 AD。与蛋白质相关的 Tau 蛋白已被深入研究，因为它在内部聚集成神经原纤维缠结。神经元是 AD 的标志之一，Tau 基因敲除在多种 AD 模型中具有保护作用。其作为 AD 治疗靶点的潜力，Tau 减少还可以防止网络过度兴奋，类似地，在这些模型中，这种情况发生在 AD 早期，可能会导致神经退行性变。神经元培养系统，Tau 减少可防止淀粉样蛋白-β (Aβ) 毒性和谷氨酸或 NMDA 诱导的简而言之，Tau 蛋白的减少在多种系统中具有保护作用，但其机制却不同。 Tau 的中央富含脯氨酸的区域在 AD 中被过度磷酸化，其作用目前尚不清楚。几个介导与包含 SH3 结构域的蛋白质（包括非受体）结合的 PxxP 基序酪氨酸激酶 Fyn 也是网络过度兴奋的重要介质，因为它磷酸化 AMPA。和 NMDA 受体来增强其信号传导并调节外源 Aβ 动力学。激活突触后密度处的 Fyn，导致神经元中 NMDAR 磷酸化和兴奋性毒性。多种证据表明 Tau 与 Fyn 的相互作用可能是 Aβ 遗传毒性的关键介质。敲除 Tau 或 Fyn 可以防止原代神经元中的 Aβ 毒性，过度磷酸化的 Tau 具有更高的对 Fyn 的亲和力，Tau 介导 Fyn 向体内树突的运输，导致 Aβ 诱导的认知缺陷然而，Tau-Fyn 相互作用是 Aβ 毒性的关键介质。尚未经过直接测试，这是我的总体假设是 Tau-Fyn。相互作用是 Aβ 诱导的结构和功能异常的关键介质，我将对此进行测试。使用 Tau-Fyn 相互作用的肽抑制剂 Tau-PxxP5/6 的假设，该抑制剂由先前的成员开发 Roberson 实验室开发了一种基于邻近连接的测定法来确认 Tau-PxxP5/6 抑制内源性 Tau-Fyn 原位相互作用，发现它可以防止 Aβ 诱导的神经突变性和膜运输在这里，我将确定 Tau-PxxP5/6 是否可以预防 Aβ 诱导的树突棘形态缺陷。使用 3D 形态测量分析以及使用多电极的 Aβ 和加巴嗪诱导的网络过度兴奋性我还将确定 Tau 的 Fyn 结合区域是否是 Tau 介导 Aβ 毒性的关键区域。通过用不同的突变 Tau 结构转导 Tau 敲除神经元来阻止 Fyn 结合。对于体外研究，我将确定 Tau-PxxP5/6 是否可以预防认知缺陷、癫痫样活动和癫痫发作使用 AD 的 hAPPJ20 小鼠模型进行体内易感性的研究将提供对 AD 的深入了解。 Aβ 毒性的分子机制，可以为治疗 AD 提供有前景的治疗策略。